Vice President Biden referred to House Republican lawmakers Thursday night as a "Neanderthal crowd" for fighting the reauthorization of his signature Violence Against Women Act.

Speaking at a reception at his official residence in Washington to mark the 19th anniversary of the law's passage, Mr. Biden told guests he was "stunned" that House Republicans put up a months-long battle over reauthorizing the law earlier this year. The GOP had concerns about new protections for Indians, gays and others.

Warning the audience that he was "going to say something outrageous," Mr. Biden said the legislation was stalled by "this Neanderthal crowd" in the House.

"I think I understand the Senate better than any man or women who's ever served in there, and I think I understand the House," he said. "I was surprised this last time. ... The idea we still had to fight? We had to fight to reauthorize?"

Mr. Biden championed the original law when he was a senator from Delaware. He when said he started writing the law in the early 1990s, "I didn't ask for staff help, I didn't ask for any help, I was so God darn — gosh darn mad."